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Mortgage Refinance Calculator
Calculate your potential savings by refinancing your mortgage. Compare your current loan payments with possible new loan terms to determine monthly savings and breakeven point.
Refinance Calculator
Enter your current loan details and the new loan terms to estimate your refinancing costs and savings.
Understanding Refinance: A Complete Guide
The refinance is one of the most significant financial decisions most Americans will make in their lifetime. With the median home price in the United States exceeding $400,000 and mortgage terms spanning 15 to 30 years, understanding every aspect of your mortgage is critical to long-term financial health.
This Refinance Calculator Calculator provides detailed analysis of your mortgage scenario, helping you understand monthly payments, total interest costs, and the true cost of homeownership. Whether you are a first-time homebuyer exploring affordability or a current homeowner considering refinancing, this tool gives you the data you need to make confident decisions.
Mortgage rates are influenced by a complex interplay of factors including Federal Reserve policy, inflation expectations, the bond market, your credit score, down payment amount, and loan type. Even a small difference in your mortgage rate — as little as 0.25% — can translate to tens of thousands of dollars over the life of a 30-year loan.
Understanding how principal and interest payments are allocated over time, how prepayments can accelerate your payoff timeline, and when refinancing makes financial sense are all essential aspects of mortgage literacy that this calculator helps illuminate.
How to Use This Refinance Calculator
- Enter your Current Loan Balance ($) — This value represents your current loan balance
- Enter your Current Interest Rate (%) — This value represents your current interest rate
- Enter your Current Loan Term Remaining (years) — This value represents your current loan term remaining (years
- Enter your New Loan Term (years) — This value represents your new loan term (years
- Enter your New Interest Rate (%) — This value represents your new interest rate
- Enter your Estimated Closing Costs ($) — This value represents your estimated closing costs
- Click Calculate — Review your results in the output section below the form. The calculator instantly computes all values based on your inputs.
- Adjust and Compare — Modify any input to see how changes affect the result. Try different scenarios to find the optimal approach for your situation.
All calculations are performed instantly in your browser. Your data is never sent to any server or stored anywhere — your financial information remains completely private.
Formula and Methodology: Mortgage Refinance Break-Even Formula
Monthly Savings = Old Payment - New Payment
Break-Even Months = Closing Costs / Monthly Savings
Total Savings = (Monthly Savings × Remaining Months) - Closing Costs
Where:
- Old Payment — Current monthly mortgage payment (P&I only)
- New Payment — New monthly payment after refinancing
- Closing Costs — Total refinancing costs (typically 2-5% of loan amount)
- Remaining Months — How many months you plan to stay in the home after refinancing
Worked Example
Current: $320,000 at 7.0%, $2,129/month, 27 years remaining. Refinance: $320,000 at 6.0%, $1,918/month, 30 years. Monthly savings: $211. Closing costs: $8,000. Break-even: 8,000 / 211 = 38 months (3.2 years). If you stay 10+ years, you save $17,320 net.
Limitations and Assumptions
Refinancing resets your loan term, which can increase total interest even with a lower rate. Compare total remaining interest on your current loan versus total interest on the new loan. Consider a shorter term refinance (e.g., 30-year to 15-year) to save significantly on total interest while building equity faster. Cash-out refinancing increases your loan balance and should be used cautiously.
Real-World Example: Putting the Refinance to Work
Let's walk through a practical home-buying scenario.
Scenario: The Martinez family is looking to buy a $350,000 home. They have $70,000 saved for a down payment (20%) and have been pre-approved at 6.75% for a 30-year fixed mortgage.
- Loan amount: $280,000
- Monthly P&I payment: $1,816
- Monthly property tax (est.): $292
- Monthly insurance: $125
- Total monthly housing cost: $2,233
- Total interest over 30 years: $373,760
By putting 20% down, the Martinez family avoids PMI (private mortgage insurance), saving approximately $117 per month. Over the first five years, they will pay approximately $88,000 in interest and only $21,000 in principal — a common surprise for new homeowners.
If they make one extra monthly payment per year ($1,816), they would pay off the mortgage in approximately 25 years and save over $62,000 in total interest. This calculator helps visualize these powerful long-term impacts.
Smart Strategies for Refinance
1. Get Pre-Approved Before Shopping
A mortgage pre-approval letter shows sellers you are a serious buyer and gives you a clear budget. It also locks in a rate for 60-90 days, protecting you from rate increases during your home search.
2. Save for a 20% Down Payment
Putting 20% down eliminates private mortgage insurance (PMI), which typically costs 0.5-1% of the loan amount annually. On a $300,000 mortgage, avoiding PMI saves $1,500-3,000 per year.
3. Compare 15-Year and 30-Year Terms
A 15-year mortgage has higher monthly payments but significantly lower total interest. On a $300,000 loan, the difference in total interest can exceed $150,000. Use this calculator to compare both options.
4. Factor in All Housing Costs
Your mortgage payment is just one component of housing costs. Property taxes, insurance, maintenance (budget 1-2% of home value annually), and utilities all contribute to your true monthly housing expense.
5. Consider Points for Long-Term Savings
Buying mortgage points (prepaid interest) reduces your rate. One point costs 1% of the loan amount and typically reduces the rate by 0.25%. If you plan to stay in the home for 5+ years, points often pay for themselves.
Scenario Comparison: Mortgage Refinance: When Does It Make Sense?
Break-even analysis for refinancing a $300,000 mortgage with $6,000 in closing costs.
| Rate Drop | Monthly Savings | Break-Even | Net Savings (10yr) | Total Interest Saved |
|---|---|---|---|---|
| 0.25% | $45 | 11.1 years | -$600 | $16,200 |
| 0.50% | $89 | 5.6 years | $4,680 | $32,040 |
| 0.75% | $133 | 3.8 years | $9,960 | $47,880 |
| 1.00% | $176 | 2.8 years | $15,120 | $63,360 |
| 1.50% | $261 | 1.9 years | $25,320 | $93,960 |
